The following relates generally to wireless communications and more specifically to mitigating interference during femtocell discovery. Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems.
Generally, a wireless multiple-access communications system may include a number of base stations, each simultaneously supporting communication for multiple mobile terminals. Base stations may communicate with mobile terminals on downstream and upstream links. Each base station has a coverage range, which may be referred to as the coverage area of the cell. In cellular deployments, the macrocell is used to describe a cell serving a wide region such as rural, suburban, and urban areas. A “femtocell” is a smaller cell, typically deployed for use in a home, small business, building, or other limited region. It often is connected to a service provider's network via a broadband connection. In 3GPP terms, femtocells may be referred to as Home NodeBs (HNB) for UMTS (WCDMA, or High Speed Packet Access (HSPA)) and Home eNodeBs (HeNB) for LTE.
For mobile terminals camped on a macrocell and approaching their femtocells, it may be desirable to have them discover and reselect to their femtocell even when the femtocell is operating on another carrier. To facilitate femtocell discovery, femtocells may transmit a beacon signal on the macrocell's frequency to cause the mobile terminal to perform an inter-frequency search. This in-band beacon signal may cause interference within the macrocell, which may degrade the capacity and user perceived performance in the macrocell. It may, therefore, be beneficial for novel femtocell architectures to be developed to mitigate the interference caused by this beacon.